Less work for the end user

Each of the principles mentioned earlier is ultimately about reducing the amount of time it takes for the user to complete a given task. The importance of task completion can't be overlooked. There's the classic study conducted by UIE back in 2001 on the impact of the time taken to complete a task on a visitor's perception of performance. Researchers sat people down in front of 10 different sites using a 56 kbps modem and gave them tasks to complete.

The surprise came when people rated the slowest site (http://www.amazon.com/) as one of the fastest when asked. The reason was that http://www.amazon.com/ allowed people to complete their tasks in fewer steps.

Ultimately, this is what it comes down to: how fast the user feels the site is. You can go a long way by implementing the performance techniques so frequently cited for developers, but to influence how your users feel about the performance of your site, performance optimization has to involve the designer.

If you...